The proposed conference will be the ninth in a series of Gordon Conferences on Heart Muscle. This series began in 1966 at the request of the Cardiac Muscle Society. Recently the focus of these conferences has broadened to include not only cardiac muscle biochemistry, physiology, and pharmacology, but also basic mechanisms of contraction seen in striated and smooth muscle. It provides the opportunity for active investigators in muscle biology from all over the world to meet and discuss current research in this field. The topic for the 1977 conference is Control of Contraction. This will bring together scientists whose tools are biophysical, biochemical, physiological, pharmacological, etc., crossing disciplinary boundaries through their interest in muscle. Topics in the recent past have included contractility, cardiac drugs, electrophysiology, smooth muscle, etc. In 1974 an excellent conference on Excitation-Contraction Coupling was held. This proposed conference is in part a sequel to that one, but with a broadened focus on all aspects of cellular control. The Gordon Conference format is conducive to free and informal exchange of ideas and unpublished data that is especially valuable in an interdisciplinary field.